SO Pulse Output + Signal Input
1-channel SO pulse output for kWh with variable pulse constant, plus an external signal input port for extended monitoring.
DEM4A20B 100 A Three-Phase DIN-Rail Energy Meter with RS485, SO Output and Signal Input
DEM4A20B is a 3P DIN-rail, direct-connected three-phase energy meter rated up to 100 A with Class B accuracy. It supports RS485 communication with Modbus RTU and DL/T 645-2007 dual protocol, 1-channel SO pulse output with variable pulse constant, and an external signal input port. MID B+D certified by SGS UK.
DIN-Rail Mounting
3P4W Direct Connection
MID B+D Certified
MID
100 A Maximum current (Imax)
3×230/400 V Rated voltage
Class B Active energy accuracy
−40°C to +70°C Operating temperature
Product Highlights
Three Phase DIN Rail Metering with Multifunction Capability
Class B Active Energy Accuracy
Class B active-energy measurement in accordance with EN 50470-3 for reliable submetering and billing applications.
RS485 Dual Protocol Communication
RS485 communication compatible with Modbus RTU and DL/T 645-2007 dual protocol, with baud rates from 9600 to 115200 bps.
Multiple Metering Modes
Supports 4 metering modes: Forward only, Reverse only, Forward + Reverse (default), and Forward − Reverse.
Full-Parameter Measurement
Measures active/reactive energy and power, voltage, current, frequency, power factor and maximum demand across all three phases.
External Signal Input Port
External signal input port enables integration with external sensors or control signals for extended monitoring applications.
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Explore ApplicationTechnical Specifications
Technical Specifications
| Voltage connection | Direct connection |
| Rated voltage | 3 × 230/400 V ±20% |
| Frequency | 50 Hz |
| Current connection | Direct connection |
| Rated current | 0.25–5(30/32/40/45/50/60) A; 0.25–10(80/100) A |
| Start current | 0.004 Ib |
| Pulse constant | 1000 imp/kWh (LED); 1000 imp/kvarh (LED) |
| Power consumption | ≤12 VA, < 1 W |
| Active energy accuracy | Class B (EN 50470-3) |
| Communication interface | IR + RS485 |
| RS485 protocol | Modbus RTU and DL/T 645-2007 (dual protocol) |
| Communication type | Bidirectional |
| RS485 configuration | Modbus address (1 to 247) Baud rate: 9600 / 19200 / 38400 / 115200 bps Parity: None / Odd / Even |
| IR port | Infrared (IR) communication for local reading |
| LCD display | 6+2, scrolling display |
| Metering function | Measures active/reactive energy, active/reactive power, voltage, current, frequency, power factor and maximum demand |
| Metering mode | 1. Total = Forward; 2. Total = Reverse; 3. Total = Forward + Reverse (default); 4. Total = Forward − Reverse |
| SO pulse output | 1-channel SO output for kWh with variable pulse constant |
| External signal input | 1 external signal input port (no high-voltage input) |
| Demand function | Interval / slip type, period 1–30 minutes (default 15 minutes) |
| Pulse width | Changeable pulse width according to current; the higher the current, the shorter the pulse width |
| Operating temperature | −40°C to +70°C |
| Average humidity | ≤75% (non-condensing) |
| IP rating | IP51 indoor |
| Protection class | Class II |
| Wiring configuration | Three-phase four-wire (3P4W) |
| Applicable standards | EN 50470-1 / EN 50470-3 |
Structure & Dimensions
DEM4A20B Dimensions & Wiring
Dimensions
Wiring
FAQ
Product FAQ
What is DEM4A20B?
DEM4A20B is a 3P DIN-rail, direct-connected three-phase energy meter rated up to 100 A with Class B accuracy. It supports RS485 communication with Modbus RTU and DL/T 645-2007 dual protocol, 1-channel SO pulse output with variable pulse constant, and an external signal input port. MID B+D certified by SGS UK.
What connection type does it use?
Direct connection, three-phase four-wire (3P4W), rated up to 100 A.
What SO pulse output does it provide?
1-channel SO output for kWh with variable pulse constant, plus an external signal input port.
What communication does it support?
RS485 communication with Modbus RTU and DL/T 645-2007 dual protocol.
What metering modes are supported?
Forward, Reverse, Forward + Reverse (default), and Forward − Reverse.
What is the certification status?
MID B+D certified by SGS UK.
Product Downloads
Product Datasheet Download
Datasheet
DEM4A Series Product Datasheet
Official DEM4A series datasheet covering product overview, specifications, wiring and dimensions.
Download PDF- Product overview and features
- Technical specifications
- Wiring diagrams and dimensions
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